Here is some additional food for thought.
At Web Directions Code I met a government employee who implemented
automatic creation of transcripts by combining a WebVTT caption file
with a WebVTT description file for a video. You can see an example at
http://dispatch.media.gbuild.net/video/14 with it being published at
http://schoolfunding.gov.au/video/school-community-forum-wollongong-nsw
in a slightly different format.
This is a prime example of an interactive transcript and it's a very
rich one since it contains both captions and descriptions.
He is being asked by many other government departments that would like
to use this in their Web sites, but are not competent enough to create
the code for this rendering themselves, even if they manage to author
the vtt files.
As a Web developer, it would be awesome if I could author such a page as:
<video controls transcript="t1">
<source src="video.webm">
<source src="video.mp4">
<track src="captions.vtt" label="english captions" kind=captions srclang="en">
<track src="descriptions.vtt" label="english descriptions"
kind=descriptions srclang="en">
</video>
<transcript id="t1">
<track src="transcript.vtt">
</transcript>
and I could use CSS to style it the way I want:
transcript ::cue(v) {
font-weight: bold;
}
No JavaScript required. Gives blind users full access to any position
in the video from the transcript.
Regards,
Silvia.